Straightening machine



April 30, 1940- B. P.'HAZELT|NE STRAIGHTENING MACHINE ts-sneet 1 gATTORNEYS.

Filed Sept. 26, 1938 WIT V5555;

April 30,v 1940- B. P. HAZELTINE 2 9.130

STRAIGHTENING MACHINE Filed Sept. 26, 1938 2 Sheets-Sheet 2 WITNESSESINVENTOR. mm. BY 6. M

M ATTORNEYS.

. j-STATES Patented A r. 30, 1940 I 'STRAIGIIITENING MACHINE IEBenjaminP; Hazeltine, Wheeling, W. Va; I Application September 26,1938,Serial nmzsihez I 17 clai s. (01. 153-54) 2 "This-inventionfrelates to.the straightening of [cylindrical blanks such as'tubing, rods and likeiarticlesbf circular cross section, and more especially to a methodandapparatus in which blanks are straightened by, the flights of rotatingscrews. The invention particularly applicable to hot straightening suchblanks; and is an improvement upon the invention disclosed in my PatentNo. 1,758,699. I n It is'amohgf the'objects ofthis invention to providea straightening method and apparatus, f of the general characterdisclosed in my abovementioned patent, in which-the blank ismoved,axiallyvas it, is being rolled. sideways, in which theldirectionj ofaxial movement is periodically reversedand'in which all of thestraightened blanks are moved axially more same direction to thesamepredetermined pointimmediately before leaving thestraighteningapparatus.

i Inacicordanc with this invention a plurality J ofblank-straighteningfscrew fiights are rotatably mounted in asubstantially horizontal parallel series and are adapted when a blankislaid ,transversely thereof --to engage it on opposite sidesatlongitudinally spaced points, thereby proyidingfa series of three.point contacts. Some of these screws have right han-d flights, and -therest have left-handflights, these right and leftjhand screws beingdriven in a common direction of thread travel andpreferablybeingdisposed in alternating relation; .The two groups of screw ,flights areadapted to periodically move verti- 'cally relativefto eachother-so'that the blankengaging portions of one group are first aboveand then below the blank-engaging portions of the. other group;Consequently, on1y one group of screws engages. a blank at a time. Theengagement of the blank on opposite sides by the screws Icreates aforward thrust, due to the rear threads, which is opposed by thereaction of the "forward threads, and becausethe blank is sup- I portedat a plurality of longitudinally spaced points its behavior correspondsto that of a .bontinuousbeam. Also, its engagement on opposite .sides byrevolving screw threads causes the blank to rotate while moving in thedirection of thread travel, so that the thrust acting upon1longitudinally,spaced points along the blank is applied progressivelyto its periphery, A straight blank moving through the threadswill besub- -,jected to no bendingstresses, because the thrust will be uniformat each point of support. In the .case of a bent or kinked blank,however, there will be created unevenly distributed stresses, due tothetendency for thepoints of support to be flights I are journaled inbearings'Z 'mounted'ony out of line, and as the blank rotates theincreased stresses applied to thebent portionsact around the blank tobring it into line. 1

Due to the fact that only one loup of screws engages the blank at atime, the blank is moved 5 axially as it is carried sideways by thescrews.

By periodically moving the other group of screws into engagement withthe blank and simultaneously removing it from (engagement with the firstgroup, its direction of axial wmovement. ,is reversed. As a result,every point along the periphery of the blank is sooner or 'latersubjected to straightening forces. Means is associated with"the'delivery ends of the screws ofnone group for raising the blankclear of the other group of screws to thereby feed it axially inonly onedirection. After this axial movement-of the blank has been arrested by astop, the blank'rolls onto a delivery table or conveyor. a

The invention isillustratedin the-accompanying drawings inwhich Fig. 1is aplan view of a preferred embodiment of apparatus for practicing myinvention; Fig. 2 is a side view .thereof; Fig. 3 is a fragmentary viewof the right end of the apparatus; Fig. 4 is an enlarged and view takenon the lineIV-IV of Fig; l'aand Fig. 5 is a diagrammatic view of amodificationof' this invention. I j

Referring to the drawings, a plurality of screw 0 horizontally spacedparallel channels 3 which form. a stationary frameworkfThe threads orflights are square and of relatively large diameter, although otherstyles of thread may be used. All of the screws mounted on this framehave threads extending in the same direction; that is, theyare alleither right or left-hand screws.

These screws are all driven in the same-direction by a common shaft 6through bevel gears 1 and 8. mounted on the shaft and screws. The screwsare adapted to receive between the vturns'of their flights a cylindricalblank 9 placed transversely of the screws. Any suitable blank feedingdevice not shown, may be used for deliveringcylindrical blanks to thescrews, and likewise any suitable receiving apparatus may be mounted atthe delivery ends of the screws to catch the blanks as they aredelivered therefrom.

A plurality of similar screws I I, having flights wound in the directionopposite to. those of screws I, are mounted between the latterpreferably in I alternating relation therewith. These screws arelikewise adapted to receive a blank between their flights however, it isa feature of this invention '55 that these screws are mounted on avertically movable frame so that they can be raised and lowered toperiodically lift a blank from the other screws and return it thereto.Accordingly, this second frame comprises a pair of horizontally spacedparallel channels l2 mounted between fixed channels 3 and rigi-dlyconnected together by transverse beams l3 (Fig. 4). These channels carrybearings 14 in which screws II are journaled. The ends of the screws areprovided with spur gears I'o which mesh with similar gears II on theintermediate screws, whereby the two groups of screws are rotated inopposite directions but their thread travel is in thesame direction. Asshown in Fig. 4, the inner or vertically movable frame is supported bymeans of depending bars l8 connected to its cross beams it with theirlower ends pivoted in the laterally projecting arms of bifurcated bellcranks l9. These cranks are rigidly mounted on horizontally spacedshafts 2| and 22 journaled in bearings 23 mounted on suitable stationarysupports. The end cranks of the two shafts are connected together bylinks 24 pivotally mounted in the lower arms of the cranks. Extendinglaterally from shaft 22 is an arm :26, the outer end of which is mountedon the top of the vertically movable piston rod ll 01' .a suitablefluid. pressure cylinder 28. When the piston is raised in the cylinderit raises this arm and thereby turns the shafts which swing the lateralarms of their bell cranks upwardly and thereby lift the movable frame.To aid the piston in this operation the frame is nearly balanced bymeans of counterweights 29 mounted on horizontal bars 3! carried by theinner ends of arms 32 projecting inwardly from shaft 22.

In the lower or inoperative position of the movable frame, as shown inthe drawings, the axes of screws I l carried by it are below the axes ofscrews I mounted on the fixed frame, but in the upper position of themovable frame the axes of its screws are above the axes of the screws ofthe other group. However, for the purpose of this invention, thismovement of the frame need be but very little because all that isnecessary is for the threads of one group of screws to lift the blankout of frictional engagement with the threads of the other group. Theblank does not need to be lifted above the threads. Such movement of theinner frame does not unmesh spur gears l6 and I! on the ends of thescrews. On the contrary, the lifting of screws H causes their gears Hito be turned slightly by gears 11, whereby the flights of screws H areturned backwardly a very short distance which substantially compensatesfor the bodily longitudinal forward movement of the screws caused bycranks l9 swinging the movable frame transversely as they raise it. i

In the use of this apparatus blank 9, delivered transversely of thescrews, is engaged on opposite sides at longitudinally spaced points byadjacent threads of each screw'of either the right or the left-handgroup, depending on which group is uppermost at the time. With thescrews rotating, the blank is rotated and simultaneously rolled orcarriedv sideways, and the resultant thrust progressively applied to theperiphery of the blank straightens it in the manner previouslyexplained. As all of the screws in each group have flights wound in thesame direction, the blank is moved axially by either group while beingcarried sideways. The result is that the bending forces exerted on it inorder to straighten it are applied progressively to its peripherythroughout its length. It is to permit this axial movement to take placecontinuously within a machine of reasonable size that the verticallymovable group of screws is provided. That is, the blank is alternatelyengaged by each group of screws, and, due to their flights being woundin opposite directions, the blank is first carried axially in onedirection and then in the other.

To cause periodic raising and lowering of the movable frame for thispurpose, pressure fluid is supplied to and exhausted from cylinder 28 bysuitable means (not shown) controlled by the axial movements of theblanks themselves. This control is preferably effected through themedium of electric flag switches mounted at both ends of the machine inthe path of the axially moving blanks. A suitable switch of thischaracter comprises a plate 36 extending transversely of the machine ateach end where it is supported for pivotal movement on a horizontal axisby means of rigid upright members 31 mounted on top of the ends of fixedchannels 3. Each plate carries on its outer face an electric contactmember 38 adapted to engage a similar contact member 39 mounted on anarm 4| projecting laterally from one of the uprights 37. One pair ofcontacts are brought together Whenever an axially moving blank strikesone of the plate 38 any place along its length and swings it outwardly.The flag switch at the right of Fig. 1 is connected by a suitableelectric circuit to the fluid supply means, and the other is connectedto the fluid exhausting means, whereby when a blank closes the righthandswitch fluid is supplied to cylinder 28 and the movable frame is liftedto cause its screws to lift the blanks from screws I and carry themtoward the opposite end of the machine. When one of the blanks strikesthe left-hand plate 36, cylinder 28 is exhausted and the weight of themovable frame causes it to fall and return the blanks to screws 1 whichagain reverse the direction of their axial travel.

Another feature of this invention is that all of the blanks aredelivered from the straightening machine at the same pointlongitudinally thereof so that they can be trimmed to the same lengths.Accordingly, means are provided for moving the blanks axially in thesame direction and to the same point regardless of whether screws H areup or down. This is preferably accomplished by enlarging the last fewthreads 42 at the delivery ends of the fixed screws I and making themshallow so that they will lift the blanks outof engagement with screws Heven when the latter are in their upper operative position. The adjacentthreads 43 of screws II are reduced in diameter to make room for theenlarged threads of screws I. As blanks at the delievery ends of thescrews can be engaged only by enlarged shallow threads 42, they can movein only one axial direction, to the right in Figs. 1 and 2. To assureall of the blanks leaving the straightening machine at the same pointlongitudinally thereof, astop is provided against which their forwardends abut before rolling off the ends of screws I. As shown in Figs. 1and 3, this stop may be formed conveniently by enlarging one of theupright members 31 so that it will extend across the path of the axiallymoving screws.

In the embodiment of the invention illustrated diagrammatically by Fig.5, a plurality of screw flights 5! are disposed in alternating relationwith a plurality of screws 52. The screws of one group have theirflights wound in one direction, while those of the other wind in theopposite direction,

direction of flight travel to rotateaand straighten the blank whileconveying it longitudinally'of the "screws, and means for periodicallyraising and but all screws are rotated in the same direction 'of flighttraveli Contraryto the first embodi- "ment of the invention', all-"ofthese screws are 'rnou'nted in fixed bearings withthe axes 53 of .5screws 4| on-the samelevel as the -.axes 54 of screws 52; Howeve'nalthough the periphery of each flight!!! is concentric with its axis 53,the

- periphery of each flight 52'is eccentric relative to its a'xis 541Consequently,=the tops-ofscrews l s i -52 are be-lo'w the-tops =ofscrews-5l -part,of;the

time, during which time a blank 59 is'eng'ag'ed "only by screws 5|;and-above the to-ps of screws "51- therest of .the'-time. As theblank-engaging portions of the eccentric screws rise aboveilike eportioiis of 'screws 5|, they lift the blank therefrom asshown in brokenlines: The blank'therefore periodically travels axially in opposite di-"rections as it is carried lengthwiseot theiscrews. This form ofthe'invention has theadvantage 2 of no lifting' frame an'd liftingmechanism, biit is not "as satisfactory--when the "amount: of axialmovement 1 of the: blank that can 'take place \between the risingand'falling 0f tlie'ec'centrio screws is insuflicient to'expose all ofthe blank directly 10 the action-of the screws. 1'19 :2 1

According tothe' provisions of the Patent Statrites, I have explainedthe principle and mode of operation of my invention and have:illustrated and describ'edwhat'l now considers to represent "its'llestembodiment." However, I desire to have it understood that, within thescope of the"- appended 'claimsjthe invention* may be practicedotherwise than as specifically illustratedvand de- "l. A "machine "forstraightening -cylin'drical *blanks; comprising "parallel rotatablymounted right andleft-handscrew flights-disposed in two groups with allflightsloflike hand in'a single transverselythereof and to engage itonopposite sides at-longitudinally spaced points; meansitfor rotatingsaid'screws to rotate and 'straighten the blank whiletconveyin'git-longitudinally o'frth'e .4 screws, and means forperiodicallyeffecting vertical movement of said groups of screwsrelative to each other whereby said blankis "operatively engaged by onlyonegrou'p at Ya timeit'o causeiit to'travelaxially alternatelyinpppositedire'ctions. i350 A machine for straightening cylindricalblanks; comprising; a group ofarparallelrotatably mounted right-handscrew flights; a group of parallel rotatably mounted left-hand-screwflights at least'so-meof'which are disposedfbetween some r 155 of therighteh'and screws; said flights being formed to "receive ablank'transversely ithereofrand .1 to engage 'it on'l opposite'i-sidesat f longitudinally "spacedpointsfmeans for. rotating said screws torotate and straighten theblank as *it is conveyed fitllongitudinally ofthe screws," and meansfor periodicallyraising and lowering'sat-vleastone-=01 said :groups of iscrews'to movertheir axes above and below theaxes of ther'screwsin the other group, whereby said blank isoperatively'engaged 'by only one group of screwsaat a time to cause itto travel axially alternately in opposite directions.

3. A machine for straightening cylindrical blanks, comprising aplurality of parallel rotatably mounted alternately arranged right andlefthand screw flights, the flights of each screw being formed toreceive a blank transversely thereof and to engage it substantially onits diametrically opposite sides at longitudinally spaced points, '75means for rotating all of saidscrews in a common ato move -their axesabove and below the axes of o the screws inthe other group, whereby saidblank *isope'ratively engaged by only one group of screws at a time tocause it to travel axially alternately lowering one of the groups ofscrews of like flight in opposite directions.

A? 4.A inachinefor straightening cylindrical l0 -blanks, comprisingparallel rotatably mounted right and left-hand screw flights disposedintwo groups with all flights of like hand in a single 'groupysaidflights being formed to receive a blank transversely thereof and toengage it on opposite in isides at longitudinallyspaced points, meansfor rotating said screws to rotate and straighten the blank wh'ile'conveying it longitudinally of the -screws," -a nd means forperiodically effecting vertical movement of said groups of screwsrelative to' each 1 other-whereby said :blank'. is Ioperatively 'engagedby only one group at a time to cause -it to: travel axially alternatelyin opposite direc- "tions, the flights at the delivery ends'nfz: the

screws of one group being shallow for raising 25 the blank out ofengagement with the other group of screws and conveying it axially.

5. A 'machine for straightening cylindrical blanks;- comprising parallelrotatably mounted right and, left-hand screw flights disposed-inriw inoppositedirections, the flights at-itherdelivery ends of the screws ofone group 'being'enlarge'd and shallow relative to the remaining flightsfor lifting the blank out "of eng'agement "with the afi other group'ofscrews and conveying it axiallyfi:

63A machine for straightening cylindrical blanks, comprising" parallelrotatably mounted right and left-handscrewflights disposed inrtwo groupswith all flights oflike hand in :a: single i0 group; said-flightsbeingformed to'receiveia blank transversely'thereof and to engage it onopposite sides at longitudinally spaced points, means for rotating'said'screws to rotate and straighten the blank while conveying itlongitudinally of the i :screws'jrneansior periodically effectingvertical movement of said groups of screws relativeto each other wherebysaid blank is operatively engaged lbyonly'one group at a time to causeit one end"ofthe' machine'for arresting said last- .65

mentioned axialmovemento-fthe blank. "71" A machine for straighteningcylindrical blanks'flcomprising a plurality of' parallel rotatablymounted alternately arranged right and lefthand screw flights, theflights of each screw be- :70 deg formed'to :receiveablank transverselythereof and to engage it onopposite sides at longitudinally spacedpoints, means for 'rotating"al1 of said' 'screwsin' a "common directionof flight travel terotatand straighten the blank wh'ile 1.7a

conveying it longitudinally of the screws, means for mounting one groupof screws of like fllght in fixed position, and means for periodicallyraising and lowering the other group of screws to periodically lift theblank from the first group of screws, whereby the blank is operativelyengaged by only one group at a time to cause it to travel axiallyalternately in opposite directions.

8. A machine for straightening cylindrical blanks, comprising aplurality of parallel rotatably mounted alternately arranged right andlefthand screw flights, the flights of each screw being formed toreceive a blank transversely thereof and to engage it on opposite sidesat longitudinally spaced points, means for rotating all of said screwsin. a common direction of flight travel to rotate and straighten theblank while conveying it longitudinally of the screws, means formounting one group of screws of like flight in fixed position, and meansfor periodically raising and lowering the other group of screws toperiodically lift the blank from the first group of screws, whereby theblank is operatively engaged by only one group at a time to cause it ingformed to receive a blank transversely thereof and to engage it onopposite sides at longitudinally spaced points, means for rotating allof said screws in a common direction of flight 'travel to rotate andstraighten the blank while conveying it longitudinally of the screws,means for mounting one group of screws of like flight in fixed position,and means for periodically raising and lowering the other group ofscrews to periodically lift the blank from the first group of screws,whereby the blank is operatively engaged by only one group at a time tocause it to travel axially alternately in opposite directions, theflights at the delivery ends of the screws of the fixed group beingenlarged and shallow for raising the blank out of engagement with themovable group of screws and conveying it axially. the adjacent flightsat the delivery ends of the screws of the vertically movable group beingreduced in diameter.

10. A machine for straightening cylindrical blanks, comprising parallelrotatably mounted right and left-hand screw flights disposed in twogroups with all flights of like hand in a single group, said flightsbeing formed to receive a blank transversely thereof and to engage it onopposite sides at longitudinally spaced points, means for rotating saidscrews to rotate and straighten the blank while conveying itlongitudinally of the screws, means for periodically effecting verticalmovement of said groups of screws relative to each other whereby saidblank is operatively engaged by only one group at a time to cause it totravel axially alternately in opposite directions, and means disposed atthe ends of the machine and actuated by engagement of the blanktherewith for periodically reversing said vertical movement effectingmeans.

11. A machine for straightening cylindrical blanks, comprising aplurality of parallel rotatarically opposite sides at longitudinallyspaced points, means for rotating all of said screws in a commondirection of flight travel to rotate and straighten the blank whileconveying it longitudinally of the screws, means for periodicallyraising and lowering one of the groups of screws of like flight to movetheir axes above and below the axes of the screws in the other group,whereby said blank is operatively engaged by only one group of screws ata time to cause it to travel axially alternately in opposite directions,andmeans disposed at the ends of the machine and actuated by engagementof the blank therewith for periodically reversing said raising andlowering means.

12. A machine for straightening cylindrical"- blanks, comprising aplurality of parallel rotatably mounted alternately arranged right andlefthand screw flights, the flights of each screw being formed toreceive a blank transversely thereof and to engage it substantially onits diametrically opposite sides at longitudinally spaced points, meansfor rotating all of said. screws in. a common. direction of flighttravel to rotate and straighten the blank while conveying itlongitudinally of the screws, means for periodically raising andlowering one of the groups of screws of like flight to move their axesabove and below the axes of the screws in the other group, whereby saidblank is operatively engaged by only one group of screws at a time tocause it to travel axially alternately in opposite directions, meansdisposed at each end of the machine for controlling the operation ofsaid raising and lowering means, and a pivotally mounted member extending across each end of the machine and adapted to actuate theadjacent controlling means when moved by an end of the blank.

13. A machine for straightening cylindrical blanks, comprisingastationary frame, a plurality of spaced parallel screw flightsrotatably mounted at their ends on said frame, a vertically movableframe mounted below said screws, a plurality of spaced parallel screwflights rotatably mounted at their ends on said movable frame betweenthe screws of the first-mentioned group, the flights of one group beingright-hand and those of the other group being left-hand and all beingformed to receive a blank transversely thereof and to engage it onopposite sides at longitudinally spaced points, means for rotating allof said screws in a common direction of flight travel to rotate andstraighten the blank while conveying it longitudinally of the screws,and means for periodically raising and lowering said movable frame tocause the screws mounted thereon to periodically lift the blank from theother group of screws and return it thereto, whereby the blank isoperatively engaged by only one group of screws at a time and therebycaused to alternately travel axially in opposite directions.

M. A machine for straightening cylindrical blanks, comprising parallelrotatably mounted right and leftdnand screw flights disposed in twogroups with all flights of like hand in a single group, said flightsbeing formed to receive a blank transversely thereof and to engage it onopposite sides at longitudinally spaced points, and means for rotatingsaid screws to rotate and straighten the blank while conveying itlongitudinally of the screws, ,the flights of one of said.

group, said flights being formed to receive a blank transversely thereofand to engage it on opposite sides at longitudinally spaced points,means for rotating said screws to rotate and straighten the blankwhileconveying it longitudinally of the screws, and means for periodicallyeffecting vertical movement of said groups of screws relative to eachother whereby said blank is operatively engaged by only one group at atime to cause it to travel axially alternately in opposite directions,and means at the delivery ends of the screws of one group for raisingthe blank out of engagement with the other group of screws and conveyingit axially.

16. A machine for straightening cylindrical blanks, comprising aplurality of parallel screw flights wound in the same direction, saidflights being formed to receive a blank transversely thereof and toengage it on opposite sides at longitudinally spaced points, means forrotating said screws to rotate and straighten the blank while conveyingit longitudinally of the screws, and periodically rising rotating meansfor lifting the blank from said flights and reversing its direction ofaxial movement.

1'7. A machine for straightening cylindrical blanks, comprising aplurality of parallel screw flights wound in the same direction, saidflights being formed to receive a blank transversely thereof and toengage it on. opposite sides at longitudinally spaced points, means forrotating said screws to rotate and straighten the blank While conveyingit longitudinally of the screws,"

and periodically rising rotating screw flights for 1 lifting the blankfrom the first-mentioned flights,

said rising flights being wound in the direction opposite to saidfirst-mentioned flights, and means for rotating said rising flights inthe direction opposite to the direction of rotation of thefirst-mentioned screws, whereby the blank travels axially alternately inopposite directions.

BENJAMIN'P. HAZELI'INE.

